Treating High Blood Pressure -- Are Two Drugs Better Than One?
January 20, 2012
By Harvey B. Simon, M.D.
There are dozens of high blood pressure drugs antihypertensives that doctors can prescribe. That's no surprise. Some 76 million Americans, about 1 of every 3 adults, have high blood pressure (also called hypertension). A similar number of people have prehypertension. But since high blood pressure causes 395,000 deaths a year in the United States, about 1 of every 6 deaths, these medicines are falling short on the job. Why?
Patients have to do their part by following important lifestyle guidelines and taking their medicines correctly. And doctors have to do a better job of prescribing antihypertensive medicines. A new approach to drug therapy can help.
Lifestyle changes are the first step in treating high blood pressure. The next step is medication.
The traditional approach is the single-drug plan. The doctor picks a drug that fits the patient's specific needs and then gradually increases the dose until the patient reaches his target blood pressure. This is called stepped care. The doctor adds a second drug only after the first medicine doesn't lower the patient's blood pressure enough, even at the highest safe dose.
The idea behind taking one drug is that the patient is exposed to fewer side effects than taking two medications at the same time. One drug should be easier to remember to take, which improves compliance. And in many cases, a full dose of one drug is less expensive than a small dose of two medications.
But often, single-drug therapy falls short. One reason is that the stepped care method was developed when the goal of treatment was a "normal" reading of 150/90. Now, however, the targets are lower. People who are in good general health apart from hypertension should bring their pressures below 140/90. Patients with diabetes, chronic kidney disease or any form of heart and artery disease should be below 130/80. It's a strict goal, and if present trends continue, target blood pressures may get even lower.
If one drug isn't enough, combination therapy is a necessity. But what about a new tactic giving two drugs from the start?
Because they are newer, ARBs were not included in the British meta-analysis. Still, four additional studies show they work well in combination with a thiazide or CCB. Similarly, although their study did not evaluate combining three drugs, the British researchers speculate that low-dose triple therapy would be more effective and safer than full-dose double therapy.
There are many ways to treat hypertension. Lifestyle therapy is always important. It may do the job for patients with mild hypertension or for others with hypertension who make major improvements in their weight, exercise or diet.
But when more help is needed, doctors can choose between traditional stepped care with one drug and low-dose combination treatment. Either way, the choice of drugs will depend on the patient's exact needs. In many cases, drug therapy will be based on taking a thiazide diuretic. But other classes of drugs may be a better choice either alone or in low-dose combinations depending on other health conditions a person has.
Whether your doctor prescribes one drug or two, your job will be to:
The new British meta-analysis suggests that two meds are better than one. Old-fashioned common sense says that two heads you and your doctor are better than one.
Harvey B. Simon, M.D. is an Associate Professor of Medicine at Harvard Medical School and a member of the Health Sciences Technology Faculty at Massachusetts Institute of Technology. He is the founding editor of the Harvard Men's Health Watch newsletter and author of six consumer health books, including The Harvard Medical School Guide to Men's Health (Simon and Schuster, 2002) and The No Sweat Exercise Plan, Lose Weight, Get Healthy and Live Longer (McGraw-Hill, 2006). Dr. Simon practices at the Massachusetts General Hospital; he received the London Prize for Excellence in Teaching from Harvard and MIT.